I’m going to be quite honest here in a constructive way. If you remove the type from your latest design approach, that mark is illegible to view as “JM” by itself. Looking at your [past work](http://www.janmense.de/arbeiten/printmedien/visitenkarten-jan-mense.html), I think you have the potential to do much better. It seems some of what you’re presenting here looks rushed or not well thought out. Have you been sketching out ideas before implementing them in Illustrator? If not, I strongly advise to do so.
Examples of great logo marks:
General Electric (GE) by Doyald Young
GP by Ged Palmer.